Device for supplying lubricating oil to molds



June 10, 1969 K N ET AL 3,448,788

DEVICE FOR SUPPLYING LUBRICATING OIL TO MOLDS Filed June 16, 1966 4 R, RoBE'HT' PTI? u a A BY RAYMOND s. szum LAS N g g o flfifiu ATTORNEY United States Patent 3,448,788 DEVICE FOR SUPPLYING LUBRICATING OIL T0 MOLDS Robert J. Keene, Chicago Heights, and Raymond S.

Szumilas, Chicago, 11]., assignors to United States Steel Corporation, a corporation of Delaware Filed June 16, 1966, Ser. No. 558,066 Int. Cl. F16n 7/ 00; B22d 11/00; B22c 3/00 US. Cl. 164-268 1 Claim ABSTRACT OF THE DISCLOSURE A lubricant-supply frame or collar adapted to rest on top of a flow-through continuous casting mold comprises a base portion and an inset portion seated thereon. The base portion has its upper surface relieved at a plurality of points spaced around the frame and inwardly from the outer edge to form laterally flaring recesses opening as elongated slots on the interior of the frame. Passages in the base portion conduct lubricant to the recesses.

This invention relates to continuous casting molds and more particularly to lubricating oil supply means for such molds.

In continuous casting of metals it is common practice to form the casting in a water-cooled open-ended tubular mold having side walls of copper or other highly heatconductive metal. Molten metal such as steel is poured into the upper end of the mold. The metal adjacent to the mold wall solidifies, and a partially solidified casting having a solidified metal shell surrounding a molten metal core is continuously withdrawn from the lower end of the mold. The metal tends to stick to the sides of the mold as it solidifies. It is essential to prevent sticking, for sticking of the casting metal to the mold may cause the thin solidified casting shell to be ruptured, resulting in a breakout, or in less aggravated cases, may cause the formation of ripples extending around the circumference of the casting. In order to prevent sticking, the mold is frequently oscillated vertically, and generally a lubricant such as rapeseed oil is supplied to the mold walls at the upper end of the mold.

Lubricating oil may be supplied through an oil supply ring at the upper end of the mold. A conventional ring includes a channel extending around the circumference of the ring, and a plurality of small round passages extending from said channel for supplying lubricating oil to the interior wall of the mold. Lubricating oil is usually supplied to this channel through a single inlet conduit. This ring structure has several disadvantages. The oil discharge passages do not supply oil evenly over the entire mold wall surface, even under ideal operating conditions. Furthermore, these passages frequently become plugged with splashing metal. The single oil inlet may result in nonuniform pressure along the channel. It may be seen that oil discharge from the channel cannot be maintained uniform along the entire length thereof.

The primary object of this invention is to provide a novel apparatus which distributes lubricating oil substantially uniformly over the entire interior wall surface of a continuous casting mold.

This and other objects will be apparent from the accompanying drawings and the description which follows:

The novel apparatus of this invention comprises a structure which includes a number of aligned wide, fiat, horizontally extending orifices which extend around the perimeter of a continuous metal casting mold above the interior walls thereof, for the purpose of delivering lubricating oil uniformly to the entire interior wall surface of the mold. In the preferred embodiment, the apparatus 3,448,788 Patented June 10, 1969 "ice comprises a body member adapted to be placed above the top of a continuous casting mold and having a central opening, inner walls extending around the perimeter of the body and facing the central opening, and a plurality of passages for lubricating oil extending transversely through the body member and terminating in aligned wide, flat horizontal orifices extending around the inner walls of the body member with only a small distance separating adjacent orifices. The central opening of the body member has essentially the same size and shape as the mold cavity in which castings are formed, and the inner walls of the body are in effect upward continuations of the interior walls of the mold. This structure makes it possible to supply lubricating oil substantially uniformly over the entire interior wall surface of the mold.

Referring now to the drawings,

FIG. 1 is a top plan view of the annular body member of this invention, with parts broken away.

FIG. 2 is a vertical sectional view taken along line 22 of FIG. 1.

FIG. 3 is a perspective view of a continuous casting mold with the annular body member of this invention.

Referring now to FIGS. 1 and 2 and especially to FIG. 1, 10 indicates a body member for delivering lubricating oil to the interior Walls of a continuous metal casting mold having a cavity of rectangular cross section in which a casting of steel or other desired metal can be formed. The body member 10 shown herein is of rectangular cross section (see FIG. 2) and has a pair of long sides 11 and a pair of short sides 12 arranged in a rectangle and defining a rectangular central opening 13 which substantially corresponds in size and shape to the cavity of the continuous casting mold with which the annular body member 10 is used. The body member 10 has a fiat horizontal base 14 (see FIG. 2) adapted to rest on top of a continuous casting mold, a fiat horizontal upper wall 15 of the same size and shape as base 14, four vertical inner walls 16 which face the central opening 13 and which are respectively aligned with the interior walls of a continuous casting mold, and four vertical outer walls 17. A conventional cover plate (not shown) may be secured to the top of upper wall 15 to protect the body member from molten metal poured into the mold.

The body member 10 is made up of four base plates 18, 19, 20, and 21, all of generally L-shaped cross section having the same cross-sectional size and shape, and four top plates 22, 23, 24, and 25, which are in interfitting engagement with base plates 18, 19, 20, and 21, respectively, and secured thereto by bolts 26. Base plate 18 and its complementary top plate 22 together form one of the long sides 11 of the body member 10. The other long side 11 is formed by base plate 20 and top plate 24. The two short sides 12 are formed by base plate 19 and top plate 23, and by base plate 21 and top plate 25. Each of the sides 11 and 12 is of rectangular cross section. The edges 27 of the base plates 18, 19, 20, and 21 make angle of 45 with the respective longitudinal directions of the base plates so that these plates can be placed in abutting edge-to-edge relationship. Adjacent base plates, e.g., 18 and 19 are welded together along their common edges 27 to provide a unitary base plate structure extending around the entire perimeter of the annular body member 10. The body member 10 is bolted to a continuous casting mold therebelow by bolts 28. The base plates 18, 19, 20, and 21 have steps formed by vertical surfaces 29 extending downwardly from the upper wall 15 of body member 10, and sloping surfaces 30 which slope gently downwardly from vertical surfaces 29 to the inner walls 16 of body member 10.

A plurality of independent transverse passages 31 for delivering lubricating oil to the interior wall of a continuous casting mold are provided in body member 10.

Each of the passages 31 includes a cylindrical inlet portion 32 extending from outer wall 17 to the sloping surface 30. Relieved portions or recesses 33 in the sloping surface 30 of base plates 18, 19, 20, and 21 form the outlet portions of passages 31. These relieved portions 33 are generally V-shaped, having their minimum width adjacent interior surface 29 and their maximum width at the inner walls 16. Lands 34 separate adjacent relieved portions 33. These lands 34 have their greatest width adjacent vertical surface 29 and taper down virtually to an apex at the inner walls 16.

Lubricating oil is supplied to the inlet ends 32 of passages 31 through tubes 35. The tubes 35 are preferably heated, particularly when rapeseed oil is used as the lubricant. Rapeseed oil is highly viscous, being virtually solid at room temperatures. Heating is necessary in order to provide sufficiently low viscosity for oil flow through the apparatus. The tubes 35 may be connected with any suitable type of oil supply manifold structure.

The inner walls 16 have a plurality of horizontally extending slotted orifices 36, which are the outlet openings of passages 30 for discharging lubricating oil into the mold. These slots 36 are arranged in aligned substantially end-to-end relationship, extending around the perimeter of body member 10, and each slot is substantially wider than the distance separating adjacent slots. Separation between adjacent slots 36 is afforded by lands 34 where they intersect the inner walls 16.

Referring now to FIG. 3, there is illustrated a continuous casting mold 40 of rectangular cross section having interior walls 41 surrounding a mold cavity of rectangular cross section. A body member of the present invention is bolted to the upper end of mold 40. The mold 40 normally includes a cover plate which covers the body member 10. This cover plate has been removed in FIG. 3 for the sake of clarity. The interior walls 41 of the mold 40 are respectively aligned with the inner Walls 16 of the body member 10. Oil delivered to the inner walls 16 of the body member 10 quickly spreads out as it issues from slots 36, so as to lubricate the entire area of mold Walls 41. The wide slots 36 and small distances separating adjacent slots result in lubrication of the entire area of the interior wall.

Lubricating oil may be supplied at any desired pressure. The pressure should be sufiicient to cause the oil to flow out through slots 36 and down the interior wall 16 of the body member 10 and thence down wall 41 of mold 40 without being sprayed into the mold cavity away from the mold walls. In the case of rapeseed oil, it is frequently necessary to use pressures in the order of 1000 to 1200 pounds per square inch in order to maintain oil flow through the apparatus. Less viscous oils require lower supply pressures.

The use of the body member herein described has the advantage that a substantially even flow of lubricating oil along the entire interior wall 41 of mold 40' is assured. The slots 36 are of a width substantially greater than the distance separating adjacent slots so that the entire surface of the mold walls 41 receives lubrication. Furthermore, the use of wide slots instead of small round openings for the discharge of lubricant minimizes the danger of plugging from splashing molten metal in the mold 30. A further advantage of the body member of this invention is that it provides a plurality of independent passages 31, each supplied from its own supply tube 35. The manifolds from which supply tubes 35 are Supplied may be sufiiciently large so that there is no appreciable pressure drop along the length of these manifolds. In this way each tube 35 receives oil at the same pressure, and the flow is uniform through all tubes 35 and passages 31. This is in contrast to prior lubricating oil supply structures, which generally consisted of an annular member having a lubricating oil channel extending around the perimeter of the member. The diameter of this channel was necessarily restricted so that pressure drop would occur along the length of the channel, with the result that the lubricant openings nearest the supply source would receive most of the lubricant, with little or no lubricant flowing through the more remote openings.

Various modifications of this invention may be made without departing from the scope and spirit of this invention.

What is claimed is: 1. A device for delivering lubricating oil to the interior walls of a continuous metal casting mold having a cavity of rectangular cross section in which a metal casting can be formed, said device comprising a body member of rectangular cross section having a rectangular central opening substantially corresponding to the cross section of the mold, including a base, an upper wall, four inside walls extending around the perimeter of said body member and facing said central opening, and four outer walls extending around the perimeter of said body member, said body member comprising four base plates of generally L-shaped cross section and four top plates of a cross-sectional shape complementary therewith,

each of said base plates having a step formed by a substantially vertical surface extending downwardly from said upper wall, a sloping surface extending downwardly from said vertical surface to said inner wall, a plurality of passageways extending from an outer wall to said vertical surface, a plurality of generally V-shaped recesses in said sloping surface, and a plurality of lands in said sloping surface separating adjacent recesses, said recesses extending from said :vertical surface to said inner wall and flaring inwardly, said passageways and said recesses, respectively, being aligned and together constituting a plurality of independent passages for lubricating oil,

each of said top plates including a substantially vertical surface and a sloping surface in engagement with the substantially vertical surface and the lands, respectively, of a base plate,

said inner walls having a plurality of horizontally extending slotted openings for discharging lubricating oil, said openings being formed by said recesses, said openings extending in aligned substantially end-toend relationship around the perimeter of said body member, the horizontal width of each slotted opening being substantially greater than the distance separating adjacent slotted openings.

References Cited UNITED STATES PATENTS 2,225,373 12/1940 Goss 16473 2,690,600 10/ 1954 Tarmann et a1. 1 164268 FOREIGN PATENTS 794,255 4/1958 Great Britain. 954,330 4/ 1964 Great Britain.

I. SPENCER OVERHOLSER, Primary Examiner.

R. SPENCER ANNEAR, Assistant Examiner.

U.S. Cl. X.R. 1841 

